September, 2013

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Forward-Looking Statement

Statements made in this presentation stating the Company’s beliefs, intentions, and expectations are forward-looking statements. The company’s actual results could differ materially from those projected. Additional information is contained in the company’s SEC filings such as our Form 10-K and Form 10-Qs filed at www.sec.gov.

Protalex, Inc.

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Protalex, Inc.

Biotechnology company focused on autoimmune diseases

Market cap: recently $75 mm; 30 mm SOS

Public company (OTC BB: PRTX) Current ownership and management structure established in

November 2009 Niobe Ventures, LLC, has invested $14 mm since 2009 and controls

79% of the equity

Lead product: PRTX-100 Staphylococcal protein A, an immuno-modulatory protein

isolated from cultured bacteria Safe and well-tolerated; three human clinical studies

completed , one in progress with > 32 RA patients dosed. Scalable and optimized GMP manufacture, 4 lots of drug

substance produced over past 5 years Protalex, Inc.

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Investment Highlights

PRTX-100 is a novel immunomodulatory biological drug candidate that may be useful in the treatment of a variety of autoimmune diseases

Proof-of-concept data from ongoing phase 1b trial in rheumatoid arthritis patients expected in early 2014

Potential efficacy in a number of orphan disease indications

Validated manufacturing process; low cost of goods relative to other biologics

Strong and growing IP positionProtalex, Inc.

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PRTX-100 Background

Highly purified Staphylococcus aureus protein A (SPA)

42 kDa bacterial membrane protein comprising five homologous 58–61 amino acid immunoglobulin binding domains Binds to Fc region of IgG Binds with high affinity to Fab framework region of Clade VH3 Igs

(most autoantibodies are VH3)

Forms unique complexes with IgG which down-regulate activated B-cells and monocyte/macrophages via FcR antibody receptors.

PRTX-100 binds to B cells with VH3 B-cell receptors

Demonstrated activity in cellular and animal models of disease

Protalex, Inc.

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PRTX-100 Reduces Footpad Swelling in Murine Collagen Induced Arthritis Model

Paw Thickness

0

0.2

0.4

0.6

0.8

1

1.2

28 31 35 38 42 45 49 52 56

Days After Immunization

Thic

knes

s C

hange

(m

m)

Female DBA/1 mice immunized with bovine collagen II, boost with CII on d21

Treat with PRTX-100 (3x/wk 0.01 mg), Etanercept (5x/wk, 100 mg) or vehicle

Histopathological scoring consistent with reduction in swelling

EtanerceptControl

PRTX-100

Protalex, Inc.

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PRTX-100 Is Not Immunosuppressive Like Anti-TNFs

Anti-TNF biologics can increase susceptibility to systemic infections by fungal pathogens, listeria, and tuberculosis FDA “Black Box” warning

We treated mice with PRTX-100, Etanercept, rabbit anti-mouse TNF, or vehicle and challenged with Listeria monocytogenes or Candida albicans

With both Listeria and Candida, infection severity and mortality was increased by anti-TNF and Etanercept but not by vehicle or PRTX-100

Full data to be presented at 2013 ACR meeting

Protalex, Inc.

-1 1 2 3 4 5 6 7 8 90

20

40

60

80

100

Vehicle

Etanercept

PRTX 50

PRTX 250

anti-TNF

STUDY DAY

PE

RC

EN

T S

UR

VIV

AL

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PRTX-1oo Inhibits Platelet Phagocytosis by Human Macrophages in vitro

In ideopathic thrombocytopenic purpura, platelets are opsonized by autoantibodies and phagocytized by macrophages in an FCgR-dependent process

In this model , PRTX-100 down-regulates FCgRI (CD16), a receptor known to have a role in macrophage activation and in phagocytosis. Protalex, Inc.

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PRTX-100 Therapeutic Hypothesis and Key Points

PRTX-100 is an immune modulator that acts through mechanisms targeting activated macrophages and certain B-cells; it is not an immunosuppressant like TNF-inhibitors or anti-CD20s

PRTX-100 is derived from fermentation of non-recombinant bacteria; at scale, cost-of-goods will be far less than that of recombinant proteins produced in mammalian cells

Dose is < 1 mg of protein, in contrast to ~ 100-fold higher dose for mAb therapeutics. Allows rapid and safe administration.

PRTX-100 may have applications in many autoimmune diseases, including rheumatoid arthritis, idiopathic thrombocytopenic purpura, and lupus

Protalex, Inc.

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Autoimmune Disease Market Opportunity

RA biologicals current market value exceeds $18 B and is growing

RA market disruptions envisioned PFE’s Xeljanz (tofacitinib) oral drug recently approved Bioequivalents to anti-TNFs and anti-CD20s in development

High value/lower cost modalities may expand current usage and may extend use of biologics from US, EU, and JP markets to global markets

Other autoimmune diseases, e.g., ITP, CIDP, bullous pemphigus, myesthenia gravis represent highly underserved indications with potential for orphan drug designation

Protalex, Inc.

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PRTX-100 Potential for Orphan Drug Designation

Adult idiopathic thrombocytopenic purpura (ITP) Incidence: 20-30 cases/million per year; patients with

platelet counts > 25,000 are rarely treated, so few require aggressive treatment

Treatments include steroids, splenectomy, thrombopoietin agonists (romiplostin and eltrombopag), high dose IVIG, and off-label, vincristine and rituximab.

Chronic inflammatory demyelinating polyneuropathy (CIDP) Incidence 10-20 cases/million per year High-dose IVIG is first line treatment, but costs >$8000

per treatment

Protalex, Inc.

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PRTX-100 Clinical Experience

2005 – IND filed for RA

2006 – Phase 1 study completed

2007 – Second Phase 1 using PRTX-100 with improved production/CMC processes

2010-11 – Phase 1b Study (PRTX-100-103) in South Africa; presented at ACR Annual Meeting in November, 2012

November 2012 – Second Phase 1b Study (PRTX-100-104), initiated in US

August 2013 – Completed fourth cohort of PRTX-100-104

Protalex, Inc.

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PRTX-100-103: Study Objectives

Primary Assess safety and tolerability of iv PRTX-100 weekly

x 4 doses

Secondary Assess immunogenicity after ≥3 doses Determine PK and estimate of PRTX-100 plasma

exposure after first and fourth dose Determine whether a relationship exists between

immunogenicity of PRTX-100 and safety and PK Assess effect of PRTX-100 on measures of disease

activity, e.g., DAS28-CRP and CDAI

Protalex, Inc.

Protalex14

PRTX-100-103: Study Design

Week:

0 1 2 3 64 108 12 16

Dosing:

ACR & DAS assessments:

Anti-SPA ABS:

90 days

PK profile:

CBC, CHEM,U/A:

Sequential Cohorts (8 active: 2 Placebo) randomized to receive 0.15, 0.45, 0.9, or 1.5 mg/kg PRTX-100 i.v.

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PRTX-100-103: DAS28 < 3.2

PRTX-100 Placebo05

1015202530

% of patients with DAS28 < 3.2 at 6 and 10 weeks

Day 42Day 70

3/29

6/29

0/8 0/8

Protalex, Inc.

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PRTX-100-103: Summary

PRTX-100 was well tolerated 3 mild to moderate infusion reactions, no SAEs related to

study drug Anti-PRTX-100 antibodies elicited in majority of patients but

neither incidence nor titer was related to dose Patients with antibody response showed increased clearance

without increase in AEs. Antibodies do not appear to preclude treatment response

Relationship between dose and Cmax was linear but clearance and AUC were variable

The higher doses of PRTX-100 resulted in low disease activity, with maximal improvement at 10 weeks after the first dose

Protalex, Inc.

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PRTX-100-104: Overview

New multi-center US study. Phase 1b randomized, multiple-dose, placebo-controlled, dose-escalation study of PRTX-100 in adults with active RA on MTX

Recent amendment calls for up to 44 patients in four dose-escalating cohorts, starting at 1.50 mg/kg, with fifth cohort to investigate extended dosing schedule

Primary objective: safety and tolerability of PRTX-100 administered by iv injections over five weeks

Secondary objectives include determining effects on measures of disease activity, assessing immunogenicity, evaluating PK, and investigating durability of response

Enrollment commenced November 2012 in the US; last dose of cohorts one through four completed July 2013; expansion cohorts initiated August 2013

Topline data to be announced 1Q14

Protalex, Inc.

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Patents and Intellectual Property

Patents (five issued in US and Japan) Initial US patent 7,211,258, “Protein A compositions

and methods of use” filed 2002 and issued 2007 Issued continuation patents expanding use to various

inflammatory diseases filed 2004, 2006, and 2010; notice of allowance for MS application received 2013

Japanese patent issued with 2023 expiration date Additional filings expected

Other Intellectual Property Considerable know-how in the manufacture and QA of

highly purified SPA expected to remain trade secret

Protalex, Inc.

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Protalex Objectives

2Q13 Safety data from first three cohorts of PRTX-100-104

3Q13 Initiation of cohort 5 extension study, to investigate monthly maintenance doses

4Q13 Filing IND for PRTX-100 in orphan indication

1Q14 Top-line results of PRTX-100-104 trial

2Q14 PRTX-100 global development strategy announcement

Protalex, Inc.

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Protalex Corporate Highlights

PRTX-100 is a novel immunomodulatory biological drug candidate that may be useful in the treatment of autoimmune diseases

PRTX-100 is economical to produce relative to anti-TNFs, anti-IL-6, and CTL4-Ig biologicals; validated manufacturing

PRTX-100 is safe and well-tolerated in humans

Safety and initial proof-of-concept data from an ongoing phase 1b trial in RA patients are expected in 2014

Protalex, Inc.